@keyframes panoramic {
    to {
        background-position: 100% 0;
    }
}

.panoramic {
    width: 150px;
    height: 150px;
    background: url('http://c3.staticflickr.com/3/2671/3904743709_74bc76d5ac_b.jpg');
    background-size: auto 100%;
    animation: panoramic 10s linear infinite alternate;
    animation-play-state: paused;
}

.panoramic:hover,
.panoramic:focus {
    animation-play-state: running;
}